Means for prevention of ice damage to boats, piers and the like



1965 J. H. o. CLARKE MEANS FOR PREVENTION OF ICE DAMAGE TO BOATS, PIERS AND THE LIKE Filed April 27. 1962 INV EN TOR JOHN H. 0; CLARKE ATTORNEYS larly in highly saline waters. V A It is known tha tias Water cools its densitydecreases until it reaches tfc. whereupon as cooling continues the MEANS FOR PREVENTION OF ECE DAMAGE T BOATS, PIERS AND THE LHKE John H. 0. Clarke, 3 Weems Creek Drive, Annapolis, Md.

Filed Apr. 27, 1962, Ser. No. 190,763

9 Claims. (Cl. 61-1) This invention relates to. ice protection and more particularly to improved method and apparatus for preventing the formation of damaging ice on piles, boats and other partially immersed objects normally exposed to damaging natural icing conditions. 7 p

Where boats, piers and the like are subjected to severe ice conditions costly damage can result unless suitable precautions are taken before the onset of the ice period.

In tidal areas, when ice forms tightly about piles, on

each rise of the tide the ice clamped about the piles raises them an increment and while they are thus suspended by the ice partly out of their original holes in the bottom, sand or mud fills in the holes beneath the piles so that when the tide falls the piles cannot return to their original position. Thus, the piles are, in effect, jacked upwardly by each rising tide until they are entirely free whereupon any structure supported on the piles collapses.

In certain northern areas of the United States heavy icing conditions are normal events and in those areas, ohjects which would be exposed to damagingj ce are gen 7 erally removed bodily from the water; for example, boats are hauled clear of the water and structures, such as piers:

and the like which are supported by piles, are dismantled and the piles jetted out and placedin storage for replace ment after the icin'g season. In more temperate parts of onfthe bottom and are supp'lied'with compressed air to i create airbubbl'es throughout the-area to 'be maintained ice-free. 'The air bubbles as they ascend towards the surface acttofdrive upwardly warmer water' which cosnares taining the temperature of this surface zone above the freezing temperature thereof.

More particularly it is the object of the invention to provide means which accomplishes the foregoing object while at the same timeit insulates the aforementioned zone which is to be maintained ice free.

Still another object of the invention is to provide method and means of the foregoing nature wherein the insulating means in addition serves as a float for the heat conducting unit so that the entire ice preventing structure maintains the same relative position with respect to the water surface regardless of the rise and fall of tide.

Still another object of the invention is to provide ice prevention means which accomplishes all of the foregoing objects by a structure formed of elongated, heat conducting material having a length capable of extending from the surface of a body of water well downwardly into the strata of warmer waters with the surface end of the material having bonded to the outer side thereof flotation material which serves not only to support the heat conducting material but also serves as an insulator against ice formed outside of the zone to be protected. I Yet another object of the invention is to provide structure of the foregoing nature which may be either prefabricated in sleeve-like form so as to slide over the upper end of individual piles and the like or may be fabricated in substantially fiat sheets which are capable of being cut to the proper size and formed as a sleeve around piles or other structures whose upper ends are not free.

Qther objects and their attendant advantages will become apparent as the following detailed description is read in conjunction with the accompanying drawings wherein: FIG. .1 is a vertical cross-sectional view illustrating one *form of the invention as it may be applied to an individua ingles with cold water at the surface toelevate its tem- L peratur'eto a level above its normal freezing temperature The so-called bubble system is effective but it is'ialso "very expensive and subject to, corrosion and otherder'angements resulting from prolonged submergence, particua modified construction of theinvention; and

pile havinga free upper end; 7

FIG, 2 is a top plan view of the arrangement of FIG. 1; FIG, 3 is aperspective view showing one manner wherebythe invention may be constructed in elongated sh'eet like form;

FIG. 4 is a vertical cross-sectional view showing one manner in which the structure of FIG. 3 may be arranged 1 for the protection of a pile whose upper end'is not free; a

FIG. 5 is a schematic side elevation showing how the structure of FIG 3 may be utilized for the protection of a'boat; r i

:FIG. 6 is a vertical cross-sectional view taken substantially on the line 6-6 of FIG. 5; 1 7

FIG. 7 is a partial vertical cross-sectional view showing FIG-8 is a view similar to FIG. '1 showing yet another modified construction of the invention,

water expands so that .lth'e colder'Water-floats'above the I at; all times above freezing or otherwise'thiswater would V Tfreeze in the same manner gas the surface waten'jand it is w recognition of the relative warmth ofthelower'. strata tein of ice prevention.

which is made useof in the above mentioned bubble sysf It is. the broad objectl-of-ithe present invention to provide novel methodland means for preventing ice forms: 7 tion against partially immersed JObjeCt'sj'With ut requiring the use of expensive, derangeablefmechanical equipment. 7 ltvis a more specific object of the present invention to provide novelmethod and meansifo'nthe prevention of rice formation. on water immersedobjects, such as piles,

Referring" now to the drawings andparticularly to FIG.

. 1', the numeral 8 designates-a conventionally driven pile located in waterssubjected to destructive icing condi trons. Ice protecting means constructed in accordance with the invention is designated 'by' the numeral 10 and 7 comprises a tubular-sleeve 12 slightly larger'in diameter than the pile '8. Bonded to thefupper outer end part of the sleeve 12 is an annular ring 14 'of water impervious heat insulating, buoyant material such as" a foamfof polystyrene, polyethylene, rubber havingclo'sed, gasified cells,

or other? suitable suhstancd Thering 14 is'b'ondedto boats and the like whichflmeanstakesadvantage ofl thef higher temperature of waterbelow the freezing layer and conducts the heat thereof into tl1e -;surface'zone "immedi ately surrounding the ojbjechtherieby continuously mainy lthesle eve l2 in "sucha position with respect 'to the upper end ofthe latter that when the assembly is floating in water the upper edge 15 ofthe sleeve is disposed 'at or.

slightly above the surface of the water for reasons that will becqmeappar'entl Further, the ring 14 0f insulating material should have a'vertica'l dimensiori'such that when 76 the assembly is inthe wa'ter theiupper andljow er'side's' 16, 1 8 ofthe ring are respectively"disposedatleast-slightly above thesurface of 'thewaterand at a'rd epth beyond the Patented Feb. 23, 1965 7 expected lower surface 19 of the ice 20; that is to say, when the protector assembly is in its position of use the ring should extend above and below the ice layer sufiiciently far so as to prevent exterior ice from touching any part of the sleeve 12. The sleeve 12 should be of a material having high thermal conductivity, such as copper or aluminum, and should extend freely below the lower edge of the ring and well into the warmer strata of water beneath the ice layer.

As should be apparent from an inspection ofFIG. 1,

when the structure of the invention is in its position of use, the lower end of the metallic sleeve 12 is totally submerged in water all of which is at a temperature above freezing, thus heat from the lower strata will be conducted through the sleeve wall toward the region of lower temperature at the upper end of the sleeve in accordance with the wellknown law of heat conductivity. Because the exterior of the sleeve in the region of greatest cold is insulated by the ring 14 from ice or freezing surface water, the annular ring of water 21 within the sleeve surrounding the pile has its temperature raised to a level which may approximate the temperature level of the warmer strata beneath the ice but in any event the temperature is raised to a level above freezing.

FIG. 4 illustrates an arrangement particularly suited for the protection of piles which support structures preventing a prefabricated sleeve from being lowered over the top of the pile as in the embodiment of FIG. 1. The structure of FIG. 4 may be identical to the structure of FIG. 1 except that the user would be required to first cut the sleeve 12 and the plastic ring 14 along a line 22 whereupon the user would spread the sleeve to an open position so that it could, in effect, be snapped around the pile below a horizontal support member, such as the stringer 24 illustrated in FIG. 4. A suitable plastic which has a sufficient degree of resiliency to permit such spreading is polyethylene foam plastic which upon being released,

elastically springs back to its original shape and aids in.

retaining the structure in its slceve-like form around the pile. In addition metallic strapping 26, 28 of the same material as the sleeve 12 may be utilized to retain the structure in its proper shape. The strapping may-be of a construction substantially similar to strapping usedto retain insulating material around pipes, that is to say, one end of the strap may be provided with'a buckle or bail through which the free end of the strap is passed and merely bent back upon itself.

In lieu of slitting the structure of FIG. 1 to provide pro tcction for piles of the type illustrated in FIG. 4, the ice protector of the invention is susceptible of fabrication in substantially fiat elongated composite sheets 2% asillustrated in FIG. 3. As shown the metallic part 30 of the sheet 29 may be corrugated, and preferably of aluminum or copper, to which there is bonded or cast at the 'upper end of the outer side thereof a continuous strip 32 of do ta'tion-plastic material which is desirably flexible, as for example, foam rubber of the type having closed cells.

With the above arrangement it will'be apparent that the user would cut off lengths as necessary for the intended For example, if a pile is to be protected ,the user wouldmeasure the circumference of the pile and would use.

cut off a length of the composite sheet 30 which is somea what greater thanirthe measured circumference and he would then bend the: sheeting around .the pile and apply suitable fasteners such as the strapping 26, 28 to produce a structure which has an appearancesimilar to that shown in FIG. 4. I 7

Boats which are subjected to ice are vulnerable fora variety of reasons but primarily because theice freezes on any, almost imperceptible, projecting fibres .orcaulking material and starts a chain reaction which may ultimately cause a substantial part of the caulkingbeing withdrawn from underwater seams resulting frequently in the ju'nex: pected sinking of a vessel'asthe ice retreats in thespring- 29 of the type illustrated in FIG. 3 is placed around the entire vessel as close inwardly to the water line as can be arranged. The surrounding sheet may be supported from the vessel by the means of lines 34 as illustrated and if necessary in order to draw the-material into the sides of the vessel as closely as possible a suitable fore and aft line 36 may be wrapped around-the entire periphery of the sheeting material to insure that only a minimum marginal band of water contacting the sides of the vessel need be raised to an above freezing temperature as explained herein before.

Where the sheeting of FIG. 3 is to be used primarily for the protection of vessels, it may be desirable to construct the plastic material as shown in FIG. 7 wherein the upper edge 33 thereof extends over the upper edge of the metallic member 40. With this arrangement it will be noted that the extending edge part 38 of the plastic material serves as a fender to prevent the upper edge of the metallic member from scarring the sides of the vessel.

In FIG. 8 a further modification of the invention is shown wherein the upper edge 42 of the heat conducting member 44 extends slightly above the upper edge of the plastic material 46. This arrangement may be useful for taking advantage of the heat of the sun as an aid in retaining an area ice free.

In addition to utilizing the conductivity of the metallic sleeve to maintain an ice-free zone about immersed objects, in tidal areas it is believed that the sleeve may also serve as a fluid conduit to direct flowing, warmer waters up into the sleeve where it co-mingles with the cooler surface water. Also as the sleeve ascends'and descends with the tide there may be an action somewhat similar to pumping whereby as the sleeve moves vertically there is a degree of turbulence set up within the confines of the sleeve which causesa certain amount of mixing of cold and warmer waters. I

The use of the invention should be apparent from the foregoing description. It is' contemplated thatthe ice protecting means of the invention will be placed in its position of use only just before the onset of icing conditions and will be removed as early as possible after the danger of ice is over. .During the winter months marine growth is dormantand the structure will remain in a maximum heat-conducting conditionfree of growth if timely placement and removal is adhered to.

It'will be apparent from the foregoing description that tively inexpensive, continuously re-usable, non-derangeable means for protecting partially immersed objects from ice damage. Tests during icing conditions utilizing polystyrene foam, which is a crumbly, quitebrittle substance, established that the invention is'elfectiveto accomplish itsintendcd purpose. It was particularly noted that even though the polystyrene 'was firmly locked in a thick ice layer which presumably expanded radially inwardly dur ing periods of extreme cold, after the ice had departed no deterioration of the foam couldbe detected, and during icing conditions there was no apparent'tenclency of thetest model to be collapsed inwardly by the pressure ofthe ice.

It will be' apparent to those skilled in the art that the structure of the invention is subject. to a variety of modifications suited to prevailing conditions. For example, the metallic member may be pleated or corrugatedsoas other plastics maybe bonded by theusoof suitable adhesives as for example,.epox adh'esiveand the like These and other materials maybe .utiliied and other changes spirit of the appended claims.,j. -What is cla'imedis:

1. Means preventing the formation office upon an 4 object partially immersed in a body of water subject to 1 v natural icing conditionscomprising metallic sheetmaterial t continuously surrounding said objectvinnclosely" spaced i "relationship With ice-free water therebetweenQwaterimpervious, heat insulating material extending continuously around the outer faceof said metallic sheet material and fixedly-securedin heat insulating 'relationshiptherewith,

said heat insulating material having continuous closing ;upper and lower terminal edges with the' zvertical dimen- Y jsion therebetween being greaterthani the thickness Of. ice

of" said. metallic, sheet material. extending substantially beyondthe lower: edge of said insulatingmaterial, and means resulting from said natural icing conditions, the lower end v t thereof terminates atfa depthno less than thebottom sur- .Inayberesorted to without departing from the scope and,

face of the layer f'of'ice resulting from said natural icing I conditions, said insulating material completely'coveri ng" thesheet material when it passes through said ice layer. 3. The means according to claim 2 Wherein said insulating 'material and said support means are. combinedin aunitary fiotatable substance having highheat insulating v properties.

'4. The means according to claim 3 wherein said in'su lating material'pomprises flotation plastic roam material.

5; The means according toclaim 4jwherein theuppei' side, edge of said plastic fo n materialioverlaps the upper. f

horizontal edgeof said sheet material to serve as a tender 7 for the edge of said heatconducting member. 151 v 7 horizontal edge part of said sheet material projects above' 6....The-nieans according to ;claim:23wherein thetupper the adjacent edge of said-heat insulating material so as l supporting said metallic sheetmat vrial. in said water with fits; upper edge "at least at the surface of the water in'its ice-free conditionandits lower end depending into heat conducting relationship inaJlowerj-strata of warm water beneath a layer of ice reisu'ltinglfrom said natural icing:

j conditions, said} insulating mateiial being so positioned on; said metallic sheet material that with thetlatter insaid supported-position the "upper edge of said'insulatin'g ma-- {terial is atleast not below the surface of the water in its l ice-free conditionand the lower edge thereof terminatesv i :at a depth no less than the bottorn'su'rface of thelaycr of ice; resulting from saidnatural 'i cing}; c'onditions,-' said J when-it passes through s'aid' ice layer.

' V metallic heat conducting member mafg'inallyfandicomi 1 form upon folding .thereofi f atmosphere,

to Y be exposed a in heat :conducting relationship with the: t

7. Theimeans according toclaim 2, wherein said sheet materialis in substantially tubular form, said material as to enable it to, be folded intojsaid form. '1 t 'i The'means according to'claim 7 including fastening 5 7 means for retaining said: sheet material said tubular i Q The-mQaIis accOrdingj to claim 7 wherei'nltsa'id sheet irnaterial is corrugated; I

30 l insulating material fleompl'e'telycoveringthe sheet material 5:15.63? bf a 'tinuously surrounding said zone; water. imperyious; heat insulating material. extending continuously around-the: outer face of said heatconducting"memberand fixedly connected injhejat, insulating relationship"therewith; said :40

, heat insulating material 'having eontinuous closing ilp'perf and ,-lower terminal" edges ;,with1,{;the, vertical' dimension,

therebetween being greater tha i theathickness of icepresulting from said natural icing conditions, the lowerI en dh of said heat' conducting'jmembenextendingisubstantiall beyond the lower d'ge of, saidinsulating,jmateriaL and" means supporting; said; heat conducting member said water with its jupper edge at least at the surfaceof the 1 water in; its ice-freexcondition and gits lowerie'nd depend in'g into heat conducting relationship in :a; lower strata of Warm water beneatha layerfjofjice resultifig from said V natural. icing conditions, s:aid in sulating material being .so positioned orij-said heat [conducting member that with the latter in its supportedposition theg uppei edge ofjsaid insulating material is at least-notjbelow the' surface of .3

its ice ree condition and the-.ilowe'rjedgetgRc ferencesfCitedihy theExaminerr UNITED STATESEATENTS;

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2,920,908 Mitchell.

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2. MEANS MAINTAINING AN ICE-FREE ZONE IN A BODY OF WATER SUBJECT TO NATURAL ICING CONDITIONS COMPRISING A METALLIC HEAT CONDUCTING MEMBER MARGINALLY AND CONTINUOUSLY SURROUNDING SAID ZONE, WATER IMPERVIOUS, HEAT INSULATING MATERIAL EXTENDING CONTINUOUSLY AROUND THE OUTER FACE OF SAID HEAT CONDUCTING MEMBER AND FIXEDLY CONNECTED IN HEAT INSULATING RELATIONSHIP THEREWITH, SAID HEAT INSULATING MATERIAL HAVING CONTINUOUS CLOSING UPPER AND LOWER TERMINAL EDGES WITH THE VERTICAL DIMENSION THEREBETWEEN BEING GREATER THAN THE THICKNESS OF ICE RESULTING FROM SAID NATURAL ICING CONDITIONS, THE LOWER END OF SAID HEAT CONDUCTING MEMBER EXTENDING SUBSTANTIALLY BEYOND THE LOWER EDGE OF SAID INSULATING MATERIAL, AND MEANS SUPPORTING SAID HEAT CONDUCTING MEMBER IN SAID WATER WITH ITS UPPER EDGE AT LEAST AT THE SURFACE OF THE WATER IN ITS ICE-FREE CONDITION AND ITS LOWER END DEPENDING INTO HEAT CONDUCTING RELATIONSHIP IN A LOWER STRATA OF WARM WATER BENEATH A LAYER OF ICE RESULTING FROM SAID NATURAL ICING CONDITIONS, SAID INSULATING MATERIAL BEING SO POSITIONED ON SAID HEAT CONDUCTING MEMBER THAT WITH THE LATTER IN ITS SUPPORTED POSITION THE UPPER EDGE OF SAID INSULATING MATERIAL IS AT LEAST NOT BELOW THE SURFACE OF THE WATER IN ITS ICE-FREE CONDITION AND THE LOWER EDGE THEREOF TERMINATES AT A DEPTH NO LESS THAN THE BOTTOM SURFACE OF THE LAYER OF ICE RESULTING FROM SAID NATURAL ICING CONDITIONS, SAID INSULATING MATERIAL COMPLETELY COVERING THE SHEET MATERIAL WHEN IT PASSES THROUGH SAID ICE LAYER. 